# encoding=utf-8

import matplotlib
import matplotlib.pyplot as plt
import numpy as np
import math

x = np.array(range(1, 10))
y1 = x.copy()
y2 = np.power(4,x) / np.power(x, 1/2)
# y = np.log2(x)

plt.title("xxx")
plt.plot(x, y1)
plt.plot(x, y2)
plt.show()
